Improved hoisting-apparatus



Y whiclra swinging spar or boom is used, said boom inted time @anni dem@ EBENEZER e. GREEN, oF EAST GLOUCESTER MASSACeiUSETTS.

Letters Patent No. 94,817, dated September 14, 1869.

IMPROVED HOISTINGAPQARATUS.. m

The Schedule referred to in these Letters Patent and making part of the same.

boom may be located anywhere upon the deck, in accordance with the pitch or list ofthe deck.

My invention consists in the employment of such movable shoe-piece, or of a series of shoe-pieces arranged With reference to movement of the boom-foot.

The drawing represents the deck o f a sloop, with a boom and its supporting-shoe arranged in accordance with my improvement.

a denotes the decksurface;

b, the mast;

c,lthe boom;

. (l d, the blocks; andV e, the tackle, by which the boom is raised to and supported at a greater or less inclination;

f g h, the-hoisting-blocks and tackle.

The foot of the boom rests in ashallow socket in a slice, t. This is the shoe that I make 'movable instead of permanent; that is to say, Ido not fasten the shoe To all whom it may concern Be it known that I, EBENEZR G. GREEN, of East Gloucester, in the county of Essex, and State of' Massachusetts, have invented Improvements in Hoisting- Apparatus; fand'I do hereby declare that the following, taken in connection with the drawings, which accompany and form part of this specification, is a description of my invention, sucient to enable those skilled in the art to practise it.

My invention has reference to the cqnstruction'of derrick-mechanism, or apparatus for raising, moving, and lowering heavy bodies, the improvement having more particular reference, however, to the arrangement ofineclianisnrfor Vloading and discharging stone into and from vessels engaged in building sea-Walls, dto.; thongli the improvement is of wider application, that is to say, it is applicable to all cranes, or hoistin moving, and lowering-crane or derrick-apparatus, in being stepped at its lower end into a socket-bearing, and having the hoisting and lowering-tackle suspended from its top end; said top end being held in position and controlled by a tackle, which connects it mast or spar-head, and enables this point of suspension to be not only swung around in a horizontal plane, but to be raised and lowered, so as to bring this point of suspension to agreatei or less distance Vfrom the post or mast.

In all hoisting and lowering-apparatus of thiskind employed upon vessels, the bottom of the boom rests and moves in a. stationary'step or `soclt-bearing o'n the deck against/.the mast, and as thedeck (when the vessel is lyingfside of a wall) is often much inclined, or lists to port or starboard, or isdown by the head or stern, great outlay of strength |is required' in swinging the stone around from the vessel to the point where it is to be lowered. l

the shoe, andkeep it from lateral displacement, but which may be readily removed, (as the vessel lists in either direction, either to starboard or to port, or lies down by the head or stern,) so as to give the'booin a tendency to swing in. the opposite direction, saving the necessary tol draw over the boom dec but I prefer the employment of one shoe, made finement at any spot where the list of the deck shall require the foot ofthe boom to rest. I claim the employment of -a several shoes, arranged to support the foot of .the boom, substantially as and for the purpose set fortlnl` V i EBENEZER G. Glw'EEN.`

Witnesses; EznA EAMES,

Gao. H. Roomse.`

to the deck, but I placebeside it cleats, k, which brace movable, and having provision for its temporary movable shoeporof 

